Heart News

Fish Oil: Friend or Foe

What are the health benefits for heart patients taking fish oil?

The American Heart Association recommends adults consume fish twice a week to gain omega-3 fatty acids to help reduce the risk of congestive heart failure, coronary heart disease, sudden cardiac arrest, and ischemic stroke, though it also advises against supplements with the oil because of a lack of health benefits. In July, the London-based Cochrane Heart Group published a study that found that scientists believe there actually may be little to no benefit taking these additives.

For this article, Courtney Kelly an Albany College of Pharmacy intern in our Clinical Pharmacy department outlines the pros and cons of fish oil supplements.

Heart health benefits

Fish oils are loaded with omega-3 fatty acids. The most common omega-3 fatty acids are called DHA and EPA. Our bodies can’t make omega-3 so it must come from our diet. It is unknown how much omega-3 fatty acids you should take daily. For healthy adults, a minimum of 250-500mg of the DHA and EPA combination is recommended but higher amounts are often recommended for certain health conditions. Patients with coronary artery disease should take at least 1,000mg per day. Patients with high triglycerides may benefit from 2,000-4,000mg per day.

Fatty fish (like salmon or tuna) and shellfish (such as oysters or crabs) are full of these omega-3’s. Some plants contain other omega-3 fatty acids that our body can convert to DHA and EPA. The American Heart Association recommends eating at least 2 servings of fatty fish per week. Below is a table containing the amount of DHA/EPA in foods known to be rich in these omega-3 fatty acids. In general, it is better to get these fatty acids from our diets, rather than a supplement.


Serving Size

Amount of DHA/EPA


1 piece of salted mackerel

4,107 mg


½ fillet

4,023 mg


6 raw oysters

565 mg

Flaxseeds (whole seeds)

1 tablespoon

2,338 mg

Flaxseed Oil

1 tablespoon

7,196 mg

Chia Seeds

1 ounce

4,915 mg


1 ounce (about 7 walnuts)

2,542 mg

Soybeans (Dry Roasted)

½ cup

1,241 mg

Why do we need these fatty acids?
Omega-3 fatty acids play an important role in brain function, growth and development, and inflammation. They even lower your triglycerides, a component of cholesterol. Deficiencies are associated with a variety of health problems, like cardiovascular disease, mood disorders, and arthritis.

Supplements: Over-The-Counter or prescription?
If you can’t get enough fish oil from your diet, supplements can be purchased over-the-counter or through the pharmacy with a prescription from your doctor. The over-the-counter products contain the same omega-3 fatty acids as the prescription options. The main difference is the concentration in the prescription-only fish oils is higher. This means you will get the same dose in fewer capsules. Additionally, the prescription versions are regulated by the FDA. Over-the-counter products are not regulated by the FDA. If you buy one of these products make sure to look for the USP seal. These medications are of higher quality than over-the-counter medications that do not have the seal.

Fish Oils: Friend

One benefit of consuming supplements over fish is knowing how many omega-3s you’re getting — that information is listed in the supplement facts label, and it’s useful when using fish oil to help with disease prevention.

Heart disease – fish oils have been shown to reduce the risk of developing heart disease, heart-related events (like heart attacks), and death in people who are at high risk of heart disease. The risk of congestive heart failure is lower in older adults with higher EPA levels.
High blood pressure – Fish oil may help lower your blood pressure. If you suffer from high blood pressure, this may be an additional benefit to you! The reduction in blood pressure seen is very small, however, and should not be used instead of your regular blood pressure lowering medications.
High triglycerides and cholesterol – Fish oils can significantly lower your triglyceride level. DHA may also increase your HDL or “good” cholesterol.
Rheumatoid Arthritis – Fish oils may help reduce pain and inflammation, improve morning stiffness, and relieve joint tenderness, in people with Rheumatoid Arthritis.

Fish Oil: Foe

Fish oil supplements are highly unstable and become rancid easily, making this one of the major drawbacks of taking fish oil supplements. What’s more, damaging free radicals form when fish oil becomes spoiled. This means rancid fish oil supplements may cause more harm than good. Common side effects of fish oils include some mild stomach upset, including indigestion or diarrhea, unpleasant taste, and bad breath.

Atrial Fibrillation – Fish oils are sometimes thought to help with diseases such as Atrial Fibrillation. Fish oils have shown to have no benefit in treating atrial fibrillation and should not be used if that is the only reason.
Cholesterol – Fish oils will not lower your LDL or “bad” cholesterol. In fact, it may raise your bad cholesterol slightly. If you have a high LDL, you need another medication, such as a statin, to help lower this.
Cognitive Decline – A common myth is that fish oils may help prevent cognitive decline in elderly patients. Research has found that fish oil does not slow cognitive decline.
Diabetes – Fish oils will not reduce your fasting glucose or A1c levels. If you have diabetes, fish oils may still be recommended to you by your doctor if your triglycerides are also elevated.

Fish oils are generally pretty safe, however too much can increase your risk of bleeding and may suppress your immune system. You should refrain from using doses greater than 3-4 grams per day. Always talk to your doctor or pharmacist before taking a medication like fish oils, especially if you are on a blood thinning medication.

Written by: Courtney Kelly, Albany College of Pharmacy & Health Sciences, Pharmacy Intern. Courtney is currently in her last year of pharmacy school at Albany College of Pharmacy & Health Sciences and currently works at Kinney Drugs. She plans to pursue a clinical pharmacy residency after graduation.